Preservative efficacy testing or "challenge testing" is performed on aqueous cosmetic and drug products to determine the minimum effective concentration of antimicrobial preservatives required for adequate preservation. Products are satisfactorily preserved if they meet appropriate acceptance criteria. Methods of preservative efficacy testing include: compendial methods, such as the United States Pharmacopoeia (USP) and the European PHarmacopoeia (EP) methods; trade association methods, such as the Cosmetic, Toiletry & Fragrance Association (CTFA) method; and rapid procedures, such as the linear regression method.1-4

Excerpt Only This is a shortened version or summary of the article that appeared in the Apr. 1, 2001 issue of Cosmetics & Toiletries magazine. The full content is not currently available online.